More recently, they were used by Saddam Hussein's Iraq against Israel and Saudi Arabia in the Gulf War.

And there are reports of their use by Libyan government forces during the civil war there in 2011.

The Scud is in many ways an "entry level" ballistic missile.

Inaccurate weapon

Indeed, the basic technology is little different from the V2 rocket developed by Nazi Germany.

The name really refers to a family of weapons with ranges of up to 300km (187 miles).

It is a short-range ballistic missile that uses liquid fuel. It is launched vertically from a small platform - usually mounted on a wheeled transporter-erector-launcher.

A ballistic missile has a high-arcing trajectory. It leaves the earth's atmosphere during the powered phase of its flight - it then goes into free-flight before the re-entry stage when it plummets back to earth.

Gyroscopes guide the rocket during the powered stage of its flight - the missile being equipped with movable fins.

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